• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 289
  • 97
  • 40
  • 36
  • 33
  • 15
  • 12
  • 9
  • 9
  • 6
  • 6
  • 4
  • 2
  • 1
  • 1
  • Tagged with
  • 741
  • 134
  • 103
  • 100
  • 77
  • 64
  • 62
  • 61
  • 58
  • 53
  • 51
  • 49
  • 49
  • 44
  • 44
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
121

Afferent vs. efferent cervical vagal nerve stimulation: effects on blood glucose, insulin, and glucagon concentrations in rats

Meyers, Erin Elizabeth 01 May 2016 (has links)
Cervical vagal nerve stimulation (VNS) has been studied in the context of several conditions including epilepsy and depression. However, its effects on glucose metabolism, and its potentially beneficial effects in type II diabetes, have not yet been evaluated in humans. Efferent parasympathetic activation reduces hepatic glucose release and increases pancreatic insulin secretion, while afferent parasympathetic activation may increase hepatic glucose release and inhibit insulin secretion potentially through sympathetic activation. Thus, the effect of combined afferent and efferent cervical VNS is difficult to predict. We hypothesized that selective efferent VNS would decrease blood glucose concentration [Glu] and that selective afferent VNS would increase [Glu]. To investigate these potentially contrasting effects of efferent vs. afferent parasympathetic signaling, we recorded [Glu] and serum insulin and glucagon levels before and during 120 min of VNS in anesthetized rats. The nerve was left intact for combined afferent and efferent VNS (n=9) or sectioned proximal or distal from the stimulation electrode for selective efferent (n=8) of afferent (n=7) VNS, respectively. We found that afferent VNS caused a strong and sustained increase in [Glu] (+108.9±20.9% or +77.6±15.4% after 120 min of combined afferent and efferent VNS or selective afferent VNS) that was not accompanied by an increase in serum insulin concentration. Combined afferent and efferent VNS significantly increased serum glucagon concentration (57.6±23.4% at 120 min of VNS), while selective afferent VNS did not increase glucagon levels. Conversely, selective efferent VNS increased [Glu] only temporarily (+28.8±11.7% at 30 min of VNS). This response coincided with a transient increase in serum glucagon concentration at 30 min of VNS (31.6±8.3%) and a strong and sustained increase in serum insulin concentration (+71.2±27.0% after 120 min of VNS). These findings demonstrate that afferent VNS may increase [Glu] by suppressing pancreatic insulin release, while efferent VNS transiently increases [Glu] by stimulating glucagon secretion before reducing levels to or below baseline values by stimulating the release of insulin. Thus, selective efferent VNS may be potentially effective in the treatment of type II diabetes.
122

THE EFFECTIVENESS OF MUSIC THERAPY INTERVENTIONS WITH PERSONS OF CONCERN: AN INTEGRATIVE REVIEW

Lauzon, Grace 01 January 2019 (has links)
Immigrants, refugees, asylum seekers, internally displaced persons, and stateless persons, collectively known as “persons of concern,” often have unmet mental health and wellness needs as a result of trauma. With a diverse variety of interventions and approaches, the use of music therapy has the potential to meet the needs of persons of concern. In the present study, the researcher conducted an integrative review to examine the use of music therapy with persons of concern. After conducting a hand-search of music therapy journals and an advanced keyword search through internet databases, the researcher found 17 studies that met inclusion criteria. There were ten studies in which participants were immigrants, six studies in which participants were refugees or asylum seekers, and one study in which participants were displaced persons. Refugees’ countries of origin were: Azerbaijan, Cambodia, Chile, Democratic Republic of Congo, Ethiopia, Iran, Liberia, North Korea, Rwanda, Sierra Leone, Sudan, and Vietnam. Immigrants’ countries of origin were: China, Haiti, India, Korea, Latin America, Malaysia, Mexico, Romania, Russia, and Vietnam. Interventions used in the studies were (in order of frequency) singing, songwriting, instrument play, improvisation, lyric analysis, music listening, music imagery, and music-based relaxation. The needs of persons of concern, music therapy interventions, the rigor and quality of music therapy research, and implications for future clinical practice are discussed.
123

Physicians Providing Alternative Medicine Boundary Crossing and the Emergence of Integrative Medicine

Lockwood, Richard Scott 01 June 2008 (has links)
Integrative medicine (IM) has organized as a new area of specialization in mainstream healthcare. The development of IM is widely attributed to popular demand for the range of therapies known collectively as Complementary and Alternative Medicine (CAM). During the 1990's the rate of acceptance of CAM accelerated among consumers, professions, financing and education. The Medical Expenditure Panel Survey (MEPS) measured CAM utilization and professional service provision during the years 1996 and 1998, but never since. These surveys were unique because they specifically inquired as to whether CAM was provided by a physician, among other types of professionals. This dissertation defines early integrative medicine (MDCAM) as CAM therapies provided by physicians. Because the MDCAM subpopulation is small, MEPS surveys for 1996 and 1998 were combined (N=39,314) to improve statistical power. The theoretical approach employed Abbott's (1988) theory of a system of professions, in which MDCAM represents a professional strategy of client differentiation through the social boundary mechanism of borrowing (Tilly, 2004) specific CAM therapies to satisfy consumer demand. The utility of the theory of a system of professions is discussed for its ability to decouple conceptual-level claims from observable workplace-level behaviors. Nearly one million Americans received CAM therapies from their physicians during the period, and this professional behavior was found in every region of the country. Services provided by physicians included spiritual healing, massage and acupuncture; national population prevalence estimates are provided. This is meaningful because physicians, at the time, were at risk for disciplinary action for providing CAM. The MDCAM subpopulation was similar to those who used both conventional and CAM services from other professional sources (BOTH), however, MDCAM reported much higher prescription medication use. The demographic profile of MDCAM was more similar to those who consume health care services frequently, compared to infrequent consumers. The MDCAM group is distinguished from those who use BOTH by increased utilization of the following services: nutritional advice, biofeedback and meditation. MDCAM is characterized by diagnoses of chronic illness. MDCAM recipients used mainstream medicine, yet employed disease management services offered by the CAM domain.
124

Spatial Genetic Structure and Local Adaptation within and among Foxtail Pine (Pinus balfouriana subsp. balfouriana) Populations Located in the Klamath Mountains, California

Piri, Rebecca D 01 January 2019 (has links)
Foxtail pine (Pinus balfouriana) is a subalpine conifer endemic to California, notably separated into two disjunct subspecies. Previous studies have described the northern subspecies,Pinus balfouriana subsp. balfouriana,as having an uncommonly high level of genetic differentiation and no discernible spatial patterns in phenotypic variation. This study seeks to characterize the spatial genetic structure and patterns of selection of the northern subspecies (Pinus balfouriana subsp. balfouriana) using genome-wide data and to identify the influence of ecology and environment on the unique genetic patterns. I show that genetic differentiation among populations is much less than previously estimated (FST= 0.000644) and there is weak isolation-by-distance structure, but ongoing gene flow is unlikely. Within populations, stand density and competitor effects contribute to inbreeding. I also show that previously measured traits are predominantly determined by genetics. Analyzing by sliding window in the genome, I show that connectivity patterns vary widely throughout the genome and identify several areas that are important to the genetic architecture of the phenotypic traits and plasticity (GxE). Overall, there is high connectivity, genetic similarity, and genetically based trait variation among and within populations of the northern subspecies of foxtail pine due to historical processes, despite biotic interactions driving inbreeding. Persistent genetic isolation, however, may make adaptation to future climate a challenge for the subspecies.
125

Nonpharmacological Techniques and Pain Management

Arbuah, Nancy 01 January 2019 (has links)
The opioid epidemic in the United States continues to be a national health crisis affecting all populations. From 1999 to 2016, more than half a million people died from drug overdose. Nonpharmacological therapies are underused in nursing practice due to the gap in nurses' baseline knowledge and confidence related to nonpharmacological techniques for pain management. The purpose of this scholarly project was to develop and implement an expert-reviewed, evidence-based education program focused on nonpharmacological techniques for pain management. Participants included 18 registered nurses (RNs) from an orthopedic unit in a large academic medical center. A 45-minute educational session was conducted for RNs. A pre/postquestionnaire, including a 5-point Likert scale on nurses' self-perceived knowledge and confidence in using selected nonpharmacological techniques, was the method of data collection. Descriptive statistics were used to analyze the data. The results indicated an increase in nurses' self-perceived knowledge in all nonpharmacological techniques. The most significant increase in knowledge posteducation intervention was guided imagery with an increase of 72% in terms of the response Good. The data analysis indicates that the nurses self-perceived confidence posteducation intervention increased in terms of the response Good by 50 % and response Excellent by 33% demonstrating the efficacy of an evidence- based education program on nonpharmacological techniques. The implications of this project for social change include the empowerment of nurses to provide holistic patient-centered care, opioid sparing in keeping in alignment with patient safety, and the development of an evidence-based program that can be replicated in other settings.
126

Handling objects in old age

Parikh, Pranav Jiteshchandra 01 December 2012 (has links)
Healthy aging influences peripheral and central levels of the neuromotor system. These age-related changes contribute to the decline in dexterous manual behavior. Difficulty in performing activities of daily living increases reliance on external assistance. Understanding specific mechanisms leading to the decline in fine manual performance is crucial for their rehabilitation. In this thesis, we have attempted to increase our awareness of the causes underlying manual disability in old age. The first study investigated how old adults apply forces and moments on a freely-movable object using a precision grip (thumb and index finger) during functionally-relevant tasks. During the grasp-lift task old adults misaligned their thumb and finger contacts and produced greater grip force, greater external moments on the object around its roll axis, and oriented force vectors differently compared with young adults. During a precision-orientation task of inserting a slot on the object over a bar (`key-slot' task), old adults were more variable in digit-tip force directions and performed the key-slot task more slowly. With practice old adults aligned their digits, reduced their grip force, and minimized external moments on the object. We conclude that with old age comes with a reduced ability to control the forces and moments applied to objects during precision grasp and manipulation. This may contribute to the ubiquitous slowing and deteriorating manual dexterity in healthy aging. Another study investigated the effects of transcranial direct current stimulation (tDCS) to the contralateral M1 combined with motor training (MP) on changes in the forces applied to the object during grasp and manipulation. We also measured performances on functional tasks in healthy elderly individuals. Our results indicate that anodal tDCS+MP facilitates retention of learning on a skillful manual task in healthy old adults. Furthermore, improved retention on the pegboard test was associated with reduced force variability on the key-slot task that demanded similar precise control over the forces applied to the object. These findings suggest that the improvement in force steadiness is one of the potential mechanisms through which short-term anodal tDCS during motor training improved performance on a functional task that outlasted the intervention period. Furthermore, anodal tDCS over M1 in combination with motor practice also influenced motor response to tasks that critically depend on sensory signals in healthy old adults. Finally, we found that, in healthy elderly individuals, the memory representations scaling the lift force for the grip and lift task generalized, while the training-based learning on the ballistic task showed an incomplete transfer to the contralateral hand. These differences may indicate task-dependent interhemispheric transfer of learning in old age. Collectively, the work presented in this thesis demonstrates that the performance on dexterous manual tasks in healthy old adults may depend on how they configure their grasp, and control their finger forces (both linear and rotational) applied to the grasped object, specifically how smooth is the applied force.
127

Starting hand position effects on arm configuration for targeted reaching movements

Ewart, Steven 01 May 2014 (has links)
No description available.
128

Optimizing motor Mmemory in healthy adults

Hussain, Sara Jeanne 01 May 2016 (has links)
Motor learning is an important component of daily life: humans are constantly adjusting their movements and acquiring new skills in order to meet the demands of their environment. Motor learning also contributes to neurorehabilitation, so it is therefore important to understand the neural mechanisms underlying motor learning so that these mechanisms can be exploited to promote neurorehabilitation after central nervous system injury. This dissertation focuses on three distinct methods of improving motor learning in healthy adults. In Chapter 2, we tested the effects of perturbation schedule on retention of a locomotor adaptation. The results of this work demonstrated that introducing a perturbation slowly and incrementally versus introducing a perturbation abruptly produces similar behavioral expression of locomotor memories across days. In Chapter 3, we tested whether administering 200 mg of caffeine immediately after practicing a novel motor skill enhances retention of that skill 24 hours later. However, we found that post-practice caffeine administration did not significantly improve retention of the motor skill. In combination with previous reports, these results suggest that the effects of post-practice caffeine administration are likely task-specific. In Chapter 4, we examined the interactions between hand use, practice-dependent plasticity and motor learning. We found that experimentally immobilizing the left hand for 8 hours facilitates subsequent practice-dependent changes in corticospinal excitability in a topographically-specific manner. In contrast, immobilization did not facilitate practice-dependent changes in TMS-evoked thumb movements, nor did it promote learning or retention of a ballistic motor skill. Although it is thought that practice-dependent changes in corticospinal excitability are an important and potentially causal contributor to motor memory, the results of this work indicate that experimentally enhancing practice-dependent changes in corticospinal excitability is not sufficient to promote motor learning. In sum, although none of the experimental interventions tested here substantially improved motor learning, these experiments highlight the influence of various mechanisms on motor learning in the intact nervous system.
129

Reduced SIRT3 contributes to large elastic artery stiffness with aging

Brodjeski, Alexander Lee 01 May 2017 (has links)
Age-related increases in arterial stiffness are mediated in part by mitochondrial dysfunction. Sirtuin 3 (SIRT3) is a mitochondrial NAD+-dependent deacetylase that regulates mitochondrial function. SIRT3 deficiency contributes to physiological dysfunction in a variety of pathological conditions. Here, we tested the hypothesis that age-associated arterial stiffness, assessed by aortic pulse wave velocity (PWV), would be accompanied with decreased renal and aortic SIRT3 expression and activity due to decreased NAD+ levels. We further tested whether boosting NAD+ concentration with nicotinamide riboside (NR), a NAD+ precursor, for 6 months would reverse the effects of aging. Old (~26 mo, n = 9) C57BL/6 male mice had higher PWV vs. young (6 mo, n = 10) (448 ± 14 vs 382 ± 13, p < 0.005), which was associated with reduced arterial SIRT3 protein (0.365 ± 0.088 AU’s vs 1.000 ± 0.000); p < 0.05). Furthermore, SIRT3 deficient male mice demonstrated higher PWV compared to age-matched control mice (480 ± 21 n = 6 vs. 391 ±12 n = 7, p < 0.005). Aortic SIRT3 protein was negatively correlated with PWV (r=-0.7798, p < 0.005). Old mice also exhibited reduced kidney SIRT3 protein (0.73 ± 0.10 AU’s) compared to young controls (1.00 ± 0.00; p = 0.0192) and reduced NAD+ (918.6 ± 50.5 pmol/mg vs. young 1302.0 ± 56.6 pmol/mg, p = 0.0036). Old mice supplemented with NR had increased NAD+ concentration in kidney tissue (1303.0 ± 90.2 pmol/mg) however, had no effect on normalizing age-associated arterial stiffness (402 ± 18 old with NR vs 418 ± 15 old; p = 0.78). Here we show for that SIRT3 protein correlates with aortic stiffness and may be required for the maintenance of healthy arteries and for the first time that supplementation with NR, a commercially available supplement, ameliorates age-associated decreases in renal NAD+ demonstrating therapeutic potential in kidney disease.
130

Status of a Translocated Florida Sand Skink Population After Six Years: Establishing and Evaluating Criteria for Success

Emerick, Adam Ryan 30 January 2015 (has links)
The translocation of organisms is becoming a frequently used tool in conservation biology. There are, however, a disproportionate number of unsuccessful attempts translocating populations of herpetofauna. Logistical and temporal limits of monitoring, combined with ambiguous metrics concerning "success," have led to few advances regarding reptile translocations. Successfully established and persistent populations are those in which both the founding population and subsequent generations show consistent or positive levels of survival and reproduction. A small population of the threatened Florida Sand Skink (Plestiodon reynoldsi) was translocated in 2007. Data collected from 2007 to 2009 confirmed survival and reproduction among the founding individuals, but the sampling did not include a long enough period to allow for the evaluation of the survival and reproduction of individuals born on the site. In this study, individuals were collected during two separate sampling events, one during the third spring and one during the sixth spring after the translocation occurred. Survival estimates, reproduction, population size and generation structure were calculated by combining and analyzing data from all years post-translocation. The numbers of both total and new individuals captured in the sixth year exceeded captures from every prior sampling event since monitoring began in 2008. Founding individuals represented only 14% of the total individuals captured, while the number of individuals born on site continued to increase. The proportion of recruits and increased number of hatchlings despite the loss of founders shows that the filial generations are producing offspring. The methods utilized in assessing this translocation effort will further the understanding of the population dynamics of the Florida Sand Skink and allow for more informed decisions in future management studies of this threatened species.

Page generated in 0.0914 seconds